The present invention relates generally to medical products. More specifically, the present invention relates to medical grade tubing and methods of connecting same in a sterile manner.
It is of course known to house medical products in containers. It is likewise known to store certain medical products, e.g., blood and blood components, in containers. It is likewise known to use tubing to: access the containers; allow for the mixing of products; and/or infuse the products into a patient. For example, it is known to collect blood products from a patient and store same in flexible plastic containers. It is also known to treat these medical products, e.g., centrifuge the blood, and combine the resultant product with other components. These products can then be infused into a patient.
In order to allow one to access the container containing a medical product or fluid, either to further treat the product, combine it with another product, add a product to the container, or infuse the product into a patient, it is known to use flexible tubes. These tubes must be made from medical grade plastics, e.g., a plastic that is inert and will not contaminate the medical product so that it can be infused or used with a patient. For example, it is known to use polyvinyl chloride (PVC) to manufacture such tubing.
At various times it may be desirable to connect one or more tubes together. Such connections preferably are made using a sterile process; otherwise, after the connection is made, it is necessary to re-sterilize the two tubes that have been connected.
Thus, sterile connection devices have been developed. One such device is available from Baxter Healthcare Corporation, Biotech North America, Deerfield, Ill. under the name xe2x80x9cSCD(copyright) 312 Sterile Tubing Welder.xe2x80x9d This connection device allows two tubes to be sterilely connected together. Briefly, the device utilizes a wafer (sealing head), that is heated to more than 500xc2x0 F. The wafer welds two separate tubing segments together. Due to the process used, contaminants are destroyed at the welding site providing a new connection that is strong enough to withstand the rigors that the product may be subject to, for example, with respect to a blood collection device- blood processing, infusing and collecting.
In the blood collection arena, such a connection device can be used to: add leukocyte filters to red cell units; pool blood products and prepare blood components using blood transfer packs; attach a sterile dock set to apheresis platelets collected with a blood cell separator; prepare aliquots for pediatric use; add different needles to sets; and other process, sample and related connection without comprising the products sterility or dating.
Although the SCD(copyright) 312 Sterile Tubing Welder provides a sterile, safe, and efficient method of connecting tubes, due to its effectiveness any polyvinyl chloride tubing can be connected to any other tubing of comparable size. This may create potential issues in that any tube, even those tubes that are coupled to products that should be not be connected to other products due to an incompatibility of the products, can be erroneously or improperly connected.
Therefore, there is a need for an improved tubing that allows for the selective connection of a tubing to another tubing in a sterile connection device.
The present invention provides tubing, and methods of connecting tubing, that allows for the connection of the tubing to similar tubes in a sterile connection device, but, does not allow the tubing to be connected to a polyvinyl chloride tubing. Thus, the tubing allows for the selective sterile connection of the tubing to only select other tubing. This therefore prevents the tubing from being connected to a polyvinyl chloride tubing preventing the connection of incompatible products or devices.
To this end, the present invention provides a medical grade tubing comprising a layer of ultra low density polyethylene that has been let down, or drawn down, in diameter approximately 10% to about 50% in an extrusion process and an inner layer of an RF active material.
In an embodiment, the tubing includes an outer layer of a polyvinyl chloride material.
In an embodiment, the ultra low density polyethylene is let down 50% in the extrusion process.
In an embodiment, the inner layer is chosen from the group consisting of ethylene vinyl acetate, polyamide alloy, and polyvinyl chloride.
In an embodiment, the tubing is co-extruded.
In an embodiment, the inner layer has a thickness of approximately 0.001 inches to about 0.010 inches, the core layer has a thickness of approximately 0.008 inches to about 0.020 inches, and the outer layer has a thickness of approximately 0.001 inches to about 0.005 inches.
In another embodiment of the invention, two medical grade tubes are provided. The tubings have been coupled together in a sterile connection device and comprising a first tubing having a core layer of ultra low density polyethylene that has been let down, or drawn down, in diameter 10% to about 50% in an extrusion process, an inner layer of an RF active material, and an outer layer of a polyvinyl chloride material, and a second tubing that does not include polyvinyl chloride.
In an embodiment, the first tubing includes an outer layer of polyvinyl chloride.
In a still further embodiment, a method for allowing for the selective sterile connection of medical grade tubing is provided comprising a first tubing comprising a core layer of ultra low density polyethylene that has been let down, or drawn down, in diameter approximately 10% to about 50% in an extrusion process and an inner layer of an RF active material, the first tube being so constructed and arranged that it can not be sterile connected to a polyvinyl chloride tubing using a sterile connection device including a heat sealing device.
An advantage of the present invention is that it allows for the selective connection of two tubes.
Still, an advantage of the present invention is that it provides proprietary tubing that cannot be connected to a standard polyvinyl chloride tubing.
Moreover, an advantage of the present invention is that it provides an improved method for connecting at least certain tubes and preventing the connection of standard PVC tubing.
Furthermore, an advantage of the present invention is that is provides an improved tubing for use in a sterile connection device.
Additional features and advantages of the present invention are described in, and will be apparent from, the Detailed Description of the Presently Preferred Embodiments and from the drawings.